Robinson annulation



The Robinson annulation is an methyl vinyl ketone.[1][2][3] It is named after Sir Robert Robinson, the British chemist who discovered it while he was at the University of Oxford.

In addition to methyl vinyl ketone, 1-chloro-3-propanone[4][5] and isoxazoles[6] will give the same product.

The methyl vinyl ketone.

Reaction mechanism

Methyl vinyl ketone (or variants thereof) are essential for the cyclohexenone ring.

Variations

Asymmetric Robinson annulation

The geranial [8]:

Wichterle reaction

The Wichterle reaction is a variant of the Robinson annulation that replaces methyl vinyl ketone with 1,3-dichloro-cis-2-butene. [9] [10] [11]

Hauser annulation

The reaction sequence in the related Hauser annulation is ortho position. The Hauser acceptor is also a Michael acceptor. In the original Hauser publication ethyl 2-carboxybenzyl phenyl sulfoxide reacts with 3-pentene-2-one with LDA as a base in THF at -78°C [13]:

The original reaction product still contains the sulfoxide group but it is lost on heating in an elimination reaction. The ultimate reaction product is a leaving group in the second.

References

  1. ^ Rapson, W. S.; Robinson, R.; J. Chem. Soc. 1935, 1285.
  2. ^ Bergmann, E. D.; Gingberg, D.; Pappo, R. Org. React. 1959, 10, 179. (Review)
  3. ^ Gawley, R. E. Synthesis 1976, 777-794. (Review)
  4. ^ Tetrahedron Lett. 1971, 12, 4995.
  5. ^ J. Org. Chem. 1984, 49, 3264. (doi:10.1021/jo00192a004)
  6. ^ McMurry, J. E. Organic Syntheses, Coll. Vol. 6, p.781 (1988); Vol. 53, p.70 (1973). (Article)
  7. ^ Organic Syntheses, Coll. Vol. 7, p.368 (1990); Vol. 63, p.37 (1985). (Article)
  8. ^ Total Synthesis and Revised Structure of Biyouyanagin A Angew. Chem. Int. Ed. 2007, 46, 4708 –4711 doi:10.1002/anie.200701552
  9. ^ Wichterle, O. et al. Coll. Czech. Chem. Commun. 1948, 13, 300.
  10. ^ Kobayashi, M.; Matsumoto, T. Chem. Lett. 1973, 957.
  11. ^ Organic Syntheses, Coll. Vol. 5, p.869 (1973); Vol. 45, p.80 (1965). (Article)
  12. ^ Recent Advances in the Hauser Annulation Mal, D.; Pahari, P. Chem. Rev.; (Review); 2007; 107(5); 1892-1918. doi:10.1021/cr068398q
  13. ^ New synthetic methods for the regioselective annelation of aromatic rings: 1-hydroxy-2,3-disubstituted naphthalenes and 1,4-dihydroxy-2,3-disubstituted naphthalenesFrank M. Hauser and Richard P.RheeJ. Org. Chem.; 1978; 43(1) pp 178 - 180; doi:10.1021/jo00395a048
 
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